Treatment of textile materials



Dec. 17, 1935. A. MELLOR ET AL 2,024,177

TREATMENT OF TEXTILE MATERIALS Filed July 24, 1933 3 she'et-s sheet 1 FIG l 2 b1 d 2 a 2 i }9 FIG .2.

FIGZ.

ALBERT MELLOR RALPH :1". mm:

ATTOENIYS Dec. 17, 1935. A. MELLOR ET AL 2,024,177

TREATMENT OF TEXTILE MATERIALS v Filed July 24, 1933 3 Sheets-Sheet 2 FIG S ALBERT MELLDR RALPH I MlmN INTO Dec. 17, 1935.

A. MELLOR ET AL TREATMENT OF TEXTILE MATERIALS Filed July 24, 1953 3 Sheets-Sheet 3 ALBERT MELLUR RALPH I MANN INVII'MGS Patented Dec. 17, 1935 UNITED STATES,

PATENT OFFICE- Application It!!! 24, 1933, No. 681,946 In Great Britain All!!! 23, 1932 13 Claims. (Cl- 101-32) This invention relates to the treatment of textile fabrics and more particularly to the production of moir effects on fabrics.

The principal object of the invention is to obtain an increased control over pattern formation in the manufacture of such fabrics, so that definite and more or less predetermined occurrence of the pattern is assured.

Apart from the production of moir effects by what is really an embossing operation, using a roller or other device engraved or otherwise provided with a simulation of a moir pattern on its surface, these effects are usually obtained by localizing pressure on the fabric at points of interference occurring between ribs in the fabric and a similarly ribbed surface, which may also be a fabric. Owing to slight irregularities of spacing existing in or imposed upon the fabric ribs, the pressure between the two surfaces is concentrated at the interference points where the two setsof ribs cross each other, and in this way the moir eifect is impressed on the fabric.

Where the moir effects are imparted by superposing the face of one fabric upon the face of the other, e. g. by doubling a fabric lengthwise, so that the protruding ribs are in contact with each other, and subjecting the fabrics to heat and pressure, the natural variation in the structure of each layer and the fact that the ribs of the two layers do not readily lie parallel to each other create a series of pressure points at the crossings of the ribs. These points crowd together under the tendency of the ribs of one surface to lie in the inter-rib spaces of the other, and the applied pressure results in a flattening of the fabric at these points to form a series of glazed lines.

A more or less predetermined wavy or eyed moir pattern can be obtained by displacing the fabric ribs before pressing so as to make the points of interference follow a more ordered plan. Such movement can be effected by hand manipulation, especially when the fabric is treated in double thickness or by guiding the fabric over the edge of a scratch board having a castellated or otherwise shaped profile before passing through the nip of the calender rolls.

The above described methods are disadvantageous both as regards the type of pattern obtainable, this being of a large open character without any kind of repeat, and because of the different intensity of the pattern on the two layers of fabric.

Greater control over the pattern can, however, be obtained by the use of an engraved roller having a ribbed surface with a spacing substantially equal to that of the fabric to be treated, this enabling eyed, i. e. closed, patterns (commonly known as Francaise" moir) to be formed and repeated alongthe length of 5 the fabric by reason of the variations in the pick-spacing of the fabric. Moreover, since the fabric is treated in single thickness, uniform intensity of pattern is obtainable. It is found, however, that unless the pick-spacing of the fab- 1o ric is very regular and the rib-spacing of the roller agrees very closely with the pick spacing (2 per inch being about the maximum possible difference), satisfactory effects cannot be obtained. Consequently, a large number of rollers 15- has to be employed to enable various patterns to be obtained and to allow for the variation which occurs between piece and piece of the fabric.

It has now been found that moir fabrics having eyed" or other patterns of predetermined and definite dimensions can be produced without relying on great regularity in the pick disposition in the fabric or close agreement between the pick spacing and the pressure rib spacing by a method which also renders it possible to create pattern repeats over any desired area and to produce substantially similar patterns on different pieces of fabric.

According to the invention a moir effect is produced by subjecting a ribbed fabric to pressure from a surface having ribs thereon which are spaced at continuously varying intervals from each other.

The spacing variation of the ribs on the surface may proceed uniformly and continuously from minimum to maximum and back to minimum, the simplest form of pressure device hav-- ing ribs whose spacing varies in the manner just indicated and run parallel to each other gen- 40 erally in the direction of the ribs in the fabric; the fabric then has its ribs displaced into curvilinear form and on being subjected to pressure by the ribbed surface receives a pattern due to the formation of pressure points where the fabric ribs cross the ribs on the surface.

If the spacing of the ribs on part of the surface is less than the rib spacing of the fabric to be treated and varies until on another part of the surface it is greater than the rib spacing of the fabric, the resultant moir pattern contains closed "eyes, as in Moir Francaise". On the other hand, if the spacing of the ribs on the surface is wholly greater than or wholly less than the rib spacing of the fabric, in other words, if

the range covered by the rib spacing of the surface excludes the rib spacing of the fabric, the pattern consists of wavy lines or bands running transverse to the fabric ribs, i. e. along the length of the fabric when the ribs are formed by the weft, as is usual.

The pressure surface can thus be used on any range of fabrics having their pick spacings wholly within the range of rib spacing on the surface to produce similar eyed moir patterns on the fabrics, or on any range of fabrics having their pick spacings either all less than the minimum rib spacing on the surface or all greater than the maximum rib spacing to produce similar noneyed patternson all the fabrics. In this way, not only may similar patterns be applied notwithstanding any small variation in pick spacing as may occur in the finishing of aparticular fabric, but substantially similar patterns may be obtained on fabrics having a considerable difference in pick spacing from the one pressure surface. The spacing of the eyes or wavy lines across the fabric is determined by the distortion of the fabric ribs, and may be controlled, as by means of a scratch board to give any predetermined pattern.

As will be understood the spacing of the ribs on the pressure surface need not vary regularly, and, moreover, portions having varying spacing may alternate with portions having uniform spacing to give corresponding variations in the patterns obtained. Again, the pressure device may have wavy ribs with varying spacing on the whole or part of its surface, this arrangement enabling patterns to be obtained even without the use of a scratch board; this method, however, does not permit as wide a range of patterns being obtained as when pick distortion is utilized, whereby the simple substitution of one scratch board for another, the pick distortion can be varied to give a great diversity of eye or wave spacings with a single straight-ribbed surface.

One form of apparatus according to the invention and patterns produced thereby will now be described with reference to the accompanying drawings in which:

Figs. 1 and 2 show diagrammatically how similar patterns are obtained using the same engraved surface on fabrics having different rib spacing;

Figs. 4 and 5 are similar to Figs. 1 and 2, and show the production of another type of pattern;

Fig. 3 shows in side elevation a scratch" board over the edge of which the fabric to be treated is drawn to distort the fabric ribs;

Fig. 6 shows the relative dispositions of the fabric being treated and the treating apparatus; and

Fig. 7 shows the production of a pattern using a modified type of engraved surface.

It being impossible in the drawings to show the actual scale of fabric rib spacing met with in practice, Figs. 1, 2, 4 and 5 of the drawings, though showing clearly the operation of the variably spaced pressure ribs to produce moir effects, are necessarily diagrammatic, the spacings of both fabric and pressure ribs being greatly reaches a minimum and commences to increase progressively and uniformly until the top e of the figure is reached. The spacing of the ribs thus varies along the face of the pressure surface, as is seen by the scale a at the left-hand side of the 5 figure.

The curved lines D b represent fabric ribs which have been distorted, as by means of the scratch board shown in- Fig. 3, into a wave form. The lines b b are evenly spaced as shown in 10 the scale b at the right-hand side of the figure. The frequent intersections of the lines a and b represent the points at which the pressure of the surface bearing the lines a falls on the fabric ribs. At these points, flattening of the fabric ribs occurs, and, as is shown by the heavy lines I, the flattened points fall on curved lines making an ordered pattern.

As will be observed from Fig. l, and particularly from the adjacent scales a, b, the distance between the fabric ribs b b is less than the distance between the lines a a at the bottom c of the pressure surface, but is greater than the distance between the lines a a at the middle d of the pressure surface, and continuing 5 upwardly again becomes less as the top e is reached. Consequently as the distance between the lines a a diminishes uniformly and progressively from the bottom 0 to the middle d, and from d increases uniformly and progressively to e, there are necessarily positions between c-d and H where the line spacing of the pressure surface equals, or substantially equals, the rib spacing of the fabric. These positions are indicated by g, h. This spacing coincidence, together with the curvature of the fabric ribs b b causes the glazed pressure points to assemble roughly in the form of closed figures. The figures thus created form an eyed or Francaise type of moir pattern.

As is clearly shown in the figure, the eyes fall on the crests of the distorted picks b, the number of eyes along the length of the fabric ribs thus being controlled by the configuration of .the scratch board by which the distortion is brought about. It will readily be understood that a similar effect could be obtained by weaving the fabric with curved picks, as by the use of a curved reed.

Fig. 2 shows a moir pattern of the same type but produced on a fabric the rib spacing of which is closer than that shown in Fig. 1, by a pressure surface having its line spacing identical with that shown in Fig. 1. Similar reference letters indicate parts similar to those in Fig. l. The scale a shows the identity of the variable spacing of the lines a with that of Fig. 1, while the scale b shows the pick spacing to be approximately in the ratio 4:5 to that of Fig. 1.

In general, eyed effects are produced when the pressure surface line spacing varies over a range greater than the spacing of the fabric ribs. Thus, for example, a single pressure surface engraved so that the line spacing varies continuously from 45 per inch to 55 per inch and back a to 45 per inch would be available to produce eyed patterns in all fabrics having rib spacings between these limits. With the same scratch board employed for all the fabrics, the patterns would be of the same character. Moreover, the one pressure surface renders possible the production of practically identical patterns on different pieces of the same type of fabric notwithstanding the small variations which may arise between the pick spacings of the pieces during operations such as dyeing.

Where the variable rib spacing of the pressure surface nowhere equals the rib spacing of the fabric, a moir effect, comprising a wavy line pattern without eyes, is obtained. Such patterns are illustrated in Figs. 4 and 5, a and 1) representing pressure ribs and fabric ribs as in Figs. 1 and 2.

The pressure rib spacing, indicated by the scales a is identical in each figure, while the fabric rib spacings, indicated by the scales 1), b, correspond to those of Figs. 1 and 2 and so are approximately in the ratio 4 :5. From the bottom c of each pressure surface, the pressure line spacing gradually diminishes to the centre (1, but never becomes equal to the fabric rib spacing and then increases to the top e.

Coincidence of the spacings never occurs, and consequently the lines of pressure points do not form closed figures, as in Figs. 1 and 2, but a series of wavy lines lying close together along longitudinal areas k; k corresponding to the spacing of the crests and valleys of the rib distortions. Thus, although the curvature of the lines of pressure points is more acute in Fig. 4 than in Fig. 5, there is obtained in spite of the different fabric rib spacing the same disposition of longitudinal areas where the pressure points are crowded together to give a glazed area merging at each side into areas with relatively little glazing. In practice, the areas have wavy edges. Moreover, the irregularities which must occur in the fabric rib distortion breaks up somewhat the edges of the glazed areas, just as with the eyed" patterns of Figs. 1 and 2 the glazed areas resulting from crowded pressure points (which are especially pronounced across the centre of each figure) merge irregularly into the areas with relatively few pressure points. Further irregularities can be imparted by having irregular variation in the pressure rib spacing, but for the sake of simplicity this spacing has been shown in the figures as varying substantially uniformly from maximum to minimum and back to maximum.

While, as previously stated, the fabric may be woven with curved ribs (picks), the manipulation essary distortions is more advantageous in that it enables a large variety of patterns to be obtained merely by the substitution of scratch boards having diiferent castellated or waved profiles. Apparatus using a scratch board is shown in Fig. 6.

As shown in the figure, a ribbed fabric'ii, e. g. a faille fabric, is led from a supply roll 9 past tension bars l0 through the nip of an engraved pressure bowl II and a paper bowl I2 to a takeup roll l3. Pressure is applied to the fabric by means of the paper bowl l2 and a further paper bowl l4 above the bowl II, the arrangement applying the pressure evenly along the nip. The pressure bowl I I may be of steel or other suitable material and is heated in any usual manner, the extent of the variation of the lines engraved thereon being selected in accordance with the rib spacing of the range of fabrics to be treated. On rotation of the bowls the fabric 8 is drawn from the roll 9 and is subjected to pressure. A scratch board I 5 having a sharp waved edge is interposed in the path of the fabric 8 between the supply roll 9 and the bowls ll, l2, so that the crests of the waves hold back the fabric while the hollows permit it to pass uninterrupted. In this way the fabric ribs are distorted just before the ribs enter the nip of the bowls and this causes the curvilinear rib disposition shown diagrammatically in Figs. 1, 2, 4 and 5.

One or more of the cycles of pressure line spacings as shown in Figs. 1 and 4 are engraved round the bowl ll, depending upon the size of repeat desired. Thus, if one cycle as in Fig. 1 is so engraved, each revolution of the bowl will impart one repeat of the eyed moir pattern to a fabric having its rib spacing within the maximum and minimum spacing of the pressure lines. Two or more equal or unequal cycles will give a corresponding number of pattern repeats for each revolution of the bowl.

There is, of course, no repeat in the pattern shown in Figs. 4 and 5, since the glazed areas run as continuous lines along the length of the fabric. In this case, it is merely necessary to provide that the pressure rib spacing only varies within limits which do not bring any of the spaces into equality with any of the rib spacings of the range of fabrics required to receive this type of pattern.

Fig. 7 shows how a moir pattern may be obtained even without the use of a scratch board by having curved pressure ribs with varying spacing. The spacing of the ribs a is shown by the scale a at the left-hand side of the figure to vary precisely as the straight ribs a of Fig. 1;

the undistorted fabric ribs b have the same spacing as the ribs b of Fig. 1, as shown by the scale b at the right-hand side of the figure. Since, as in Fig. 1, the pressure rib spacing is in parts of the surface greater than the fabric rib spacing, and in other parts less, the resultant moir pattern is very similar to that of Fig. 1. Similarly, patterns similar to that of Fig. 4 can be obtained by using the pressure surface of Fig. 7 on a fabric the rib spacing of which never equals the pressure rib spacing. Further, the pressure surface of Fig. 7 could be used with a scratch board to give more varied patterns.

By reason of the bowl being adapted for treating fabrics of greatly varying pick spacing it is not necessary to hold a large stock of slightly.

different bowls in order to deal with a comprehensive range of fabrics. The invention, therefore, allows of a low capital outlay to cover a large range of cloths.

While suitable for the production of moir effects on ribbed silks and textile materials generally, the pressing device according to the invention is particularly useful in its application to ribbed fabrics made of or containing yarns of organic derivatives of cellulose, such as cellulose acetate, cellulose formate, cellulose propionate and cellulose butyrate, and cellulose ethers such as ethyl cellulose, methyl cellulose and benzyl cellulose. Because of the thermoplastic character of these materials, the moir effect produced is substantially permanent in character.

The application of the pattern can, moreover, be facilitated, and its permanence increased if prior to, or during treatment, suitable softeners for the organic derivatives of cellulose are sprayed upon or otherwise applied to the fabric. Examples of such softeners are acetone and methyl acetate, suitably diluted so as to act as softening agents only and not as solvents for the organic derivative of cellulose. Other suitable substances are triacetin, para-toluene sulphonamide or its derivatives, diethyl phthalate, para-toluene sulphonanilide and high boiling alkylated xylene-suiphonamide derivatives (e. g.

men-methyl xylene sulphonamide). Instead of 7 spraying the fabric to be treated, the fabric can be passed through a bath containing up to 40-50% of an aqueous solution of acetone, any excess of acetone solution beingremoved as by passing the fabric between rolls, so as to leave the fabric damped with the acetone solution. Such treatment with a softener, moreover, enables the operation to be carried out at lower temperature and pressure.

What we claim and desire to' secure by Letters Patent is:-- v

1. Process for the production of moir fabric, which comprises subjecting a ribbed fabric to pressure along a series of linesQextending in the general direction of. the ribs and spaced at progressively varying intervals from each other, at least one of the series of lines represented by the ribs of the fabric and by the pressure lines, respectively, being curvilinear.

2. Process for the production of moir fabric, which comprises subjecting a ribbed fabric to pressure along a series of curved lines extending in the general direction of the ribs and spaced at progressively varying intervals from each other.

3. In a process for the manufacture of moir fabric by localizing pressure on a ribbed fabric at points of interference occurring between the ribs of fabric and series of lines extending in the general direction of the ribs, the step of effecting the localized pressure by subjecting the ribbed fabric to pressure along a series of'lines which are spaced at progressively varying intervals from each other.

4. In a process for the manufacture of moir fabric by localizing pressure on a ribbed fabric at points of interference occurring between the ribs of the fabric and a series of lines extending in the general direction of the ribs, the step of producing a closed eye moir pattern which comprises effecting the localized pressure by subjecting the ribbed fabric to pressure along a series of lines which are spaced at progressively varying intervals from each other over a range covering the rib spacing of the fabric.

5. In a. process for the manufacture of moir fabric by localizing pressure on a ribbed fabric at points of interference occurring between the ribs of the fabric and a series of lines extending in the general direction of the ribs, the step of producing a waved moir pattern which comprises effecting the localized pressure by subjecting the ribbed fabric to pressure along a series of'lines which are spaced at progressively varying in- 5 tervals from each other over a range excluding the rib spacing of the fabric.

6. The manufacture of'moir fabric comprising distorting the ribs of a ribbed fabric and then subjecting the fabric to pressure from a surface having ribs thereon which are spaced at progressively varying intervals from each other.

'7. The manufacture of moir fabric comprising distorting the ribs of a ribbed fabric and then subjecting the fabric to pressure from a surface having ribs thereon which are spaced at progressively varying intervals from each other, said pressure ribs lying in the general direction of the ribs of the fabric.

8. A pressure surface for use in the production of moir fabrics, said surface having ribs which are spaced at progressively varying intervals from each other. 7

9. A pressure roller for use in the production of moir fabrics, said roller having on its surface ribs which are spaced at progressively varying intervals from each other.

10. A pressure roller for use in the production of moir fabrics, said roller having on its surface ribs the spacing of which varies progressively from a minimum to maximum and back to minimum.

11. A pressure roller for use in the production of moir fabrics, said rol'ler having on its surface ribs the spacing of which varies progressively from a minimum to maximum and back to minimum, to form a cycle of spacing variations extending completely round the circumference of the roller.

12. A pressure surface for use in the production of moir fabrics, said surface having curved ribs 40 which are spaced at progressively varying intervals from each other.

13. A pressure roller for use in the production of moir fabrics, said roller having on its surface curved ribs which are spaced at progressively varying intervals from each other.

ALBERT MELLOR. RALPH JAMES MANN. 

